There are many situations where it is desirable to mix together two or more components to form a mixture that gets applied to form a structural component. For example, many structural items are formed from a polyurethane-based foam that is formed by mixing a urethane resin based liquid with a catalyst. When the two components mix they react to form a foam that causes the mixture to expand and eventually dry and harden into a structural element. These structural elements might include building insulation, molded foam products, and other items. In these situations it is necessary to carefully control the temperature, pressure, and flow rate of the materials being mixed.
A popular material for insulating commercial buildings and residential buildings is spray foam insulation. To create the spray foam insulation, two liquid components are mixed together as they are sprayed. As the two components mix together, they foam and expand and then relatively quickly dry and harden into a permanent insulation layer. The first liquid is commonly referred to as part A or component A and is typically comprised of isocyanates. The second component is typically referred to as part B or component B, and is typically a polymer resin. When component A and component B are mixed together at an elevated temperature, an immediate chemical reaction begins that releases gas that forms bubbles in the mixture. The mixture quickly hardens into a foamed solid.
In order to effectively apply such plural component insulations it is necessary to carefully control the temperature, pressure, and ratio of component A and component B as they are sprayed. If theses variables are not carefully controlled, it can result in an inefficient or wasteful use of the components, the resulting insulation product may be inferior, and the spraying equipment may be damaged. It can be difficult to optimally control these variables. The optimal inputs can vary during a single spraying session based on temperature changes—both environmental temperatures and equipment temperatures, especially as the equipment fully warms up. In the past, pressures have been adjusted by a user based on their observations of the quality of the foam. Electro-mechanical relay systems for operating check valves have been suggested for balancing the pressures of the two components as they are applied.
The efficient heating of the components to the appropriate temperature can be important. It is desirable to heat the components in a manner that is fast, and that maximizes the efficiency of the energy consumed in producing heat. In addition to heating the components, energy is required for moving the components through the system and ultimately to spray the components into place.
From the perspective of an owner of a spray rig, one of the important factors in how profitable operating the rig can be is the efficiency of the crew operating the rig. However, unless the owner is present, it can be difficult for the owner to know how efficient a crew is in their operation of the rig. For example, the efficiency could be better estimated if the owner knew how much time the crew spent spraying versus how much time was idle at a job site. Furthermore, there is danger that users of the system will “moonlight” by using the equipment at unauthorized jobs for which the owner is not being paid. Better yet would be if the owner could track the activity of the spray rig in real time from a home office.
When a mixing system, such as a spray foam insulation rig, shuts down for a long idle period between jobs, it is necessary to park the system. In particular, the pumps need to be returned to a “wet” rest position to avoid any material remaining in the pumps that could harden or crystallize and damage the pumps when they are restarted. The pressure should also be released from the system to avoid stress on the parts and to permit cleaning of the hoses and guns. Typically this is a manual process.
The components are supplied to the spray gun by a hose that includes a bundle including at least a conduit for each component. It is known to heat the conduits within the hose by using electrical resistance heaters. More recently, it has been realized that heated glycol or similar heat containing liquid can be provided to the hose to help maintain the A and B components at the proper temperature as they travel through the hose to the gun. Unfortunately, these heated hoses have been heavy and cumbersome both in storage and in use.
The present invention is an improvement over existing plural component spray rigs. It is an object of the present invention to improve the efficiency of the operation of a spray rig by automatically balancing at an appropriate ratio the pressure at which component A and component B are provided to a spray gun.
It is a further object of the present invention to efficiently heat component A and B by utilizing the heat generated by the engine and air compressor that are used to power the spray rig to provide heat to the components A and B.
It is a further object of the present invention to improve the efficiency of a spray rig by utilizing an air compressor to drive the pumps and other mechanisms used to move the components A and B through the system as well as to clear the components from the spray gun.
It is a further object of the present invention to record and log the spraying activity of the system to permit the efficiency of its use to be monitored.
It is a further object of the present invention to record and log the GPS coordinates of the spray rig as it is being used to monitor the use of the spray rig.
It is another object of the present invention to provide an automated system for returning the pump to a storage position and bleeding pressure from the system to when parking the system between jobs.
It is another object of the present invention to permit real time monitoring from a remote location of the activity of a mixing system.
It is a further object of the present invention to transfer data from the mixing system to a remote location.
It is yet another object of the present invention to permit control and reprogramming of the system from a remote location.
It is yet another object of the present invention to provide a lighter-weight heated hose for use transporting the components to the spray gun.
These and other advantages will be realized by the embodiments of the invention described and claimed herein. It should be understood that some embodiments may accomplish only one or a few of the objects. The invention should not be limited by the listed objects, except as reflected in the language of the claims.